The regulation of pancreatic acinar function by insulin is being studied using isolated pancreatic acini prepared from normal and diabetic rats and mice. The effects of insulin alone and modification of the response to pancreatic secretagogues, cholecystokinin and acetylcholine, are being studied. Stimulation of glucose transport in acini is being analyzed using 3H-2 deoxyglucose. Insulin receptors on acini are being characterized by studying the binding of iodinated insulin. The content and secretion of pancreatic enzymes is being studied in normal and diabetic tissue. A major aim is to determine the mechanism by which insulin regulates the content of amylase. Preliminary studies show that insulin stimulates incorporation of amino acids into protein without an effect on amino acid transport. During the next year we plan to determine the effects of insulin on identified pancreatic proteins.